// 水滴自上而下的融合效果
.drop-box {
  display: flex;
  justify-content: center;
  align-items: center;
  flex-direction: column;
  filter: contrast(30);

  .drop {
    width: 100px;
    height: 100px;
    background-color: #fff;
    border-radius: 50%;
    position: absolute;
    filter: blur(20px);
    opacity: 0;
    animation: 2.5s drop linear infinite;
  }

  .drop:nth-child(2) {
    animation-delay: .5s;
  }

  .drop:nth-child(3) {
    animation-delay: .7s;
  }

  .collection {
    width: 100px;
    height: 100px;
    background-color: #fff;
    border-radius: 50%;
    filter: blur(20px);
    animation: 3s collection linear infinite;
  }

  .text {
    position: absolute;
    font-family: Helvetica;
    font-size: 30px;
  }

  @keyframes drop {
    0% {
      transform: scale(.7) translateY(-600%);
      opacity: 0;
    }

    50% {
      transform: scale(.4) translateY(-80%);
      opacity: 1;
    }

    100% {
      transform: scale(.3) translateY(0px);
    }
  }

  @keyframes collection {
    0% {
      transform: scale(1) rotate(0deg);
    }

    50% {
      transform: scale(1.3) rotate(180deg);
      width: 90px;
      border-top-left-radius: 40%;
      border-bottom-left-radius: 45%;
    }

    100% {
      transform: scale(1) rotate(360deg);
    }
  }
}